To improve quality of a wireless communications terminal, metal is increasingly widely applied to appearance design of a mobile phone. Wireless communications is an indispensable function of a wireless device, and an antenna is an indispensable component of a wireless communications terminal. A level of antenna performance is related to various types of wireless communication performance of the wireless communications terminal. For example, antenna performance of a mobile phone affects call quality of a user of the mobile phone. However, based on inherent performance of metal and an antenna, the metal has relatively large impact on performance of the antenna of the wireless communications terminal. Therefore, how to design a high-performance antenna based on a metal appearance becomes a research topic in the industry.
In the prior art, for a wireless communications terminal that has metal-appearance design, slitting processing is performed on one side of a closed frame of the wireless communications terminal, a radio frequency feeder performs feeding excitation on a slit, and the closed frame is utilized, to form a loop antenna. However, because the wireless communications terminal is generally handheld by a user for use, for the foregoing wireless communications terminal in which the closed frame is utilized to form the loop antenna, electric intensity of antenna radiation is strong in the slit of the closed frame. When a hand of the user holds the slit, problems such as frequency offset occur in working resonance of the antenna, which causes a sharp decrease in antenna performance. For example, when the user of the mobile phone uses the mobile phone for a call, if a hand of the user of the mobile phone holds the slit of the slit antenna, phenomena including call drop, suspension, and the like may occur in a call process, which affects use experience of the user.